Journal of Solar Energy Research
Volume:4 Issue: 1, Winter 2019

Given the increasing popularity of solar energy and producing its accessory equipment in Iran, like DC/DC converters, and since for studying and comparing converter’s performance or developed algorithms to extract the maximum power from converter, it is necessary to test it under uniform conditions, but due to various interfering factors such as hourly, daily, and spatial variation of solar radiation intensity or unpredictable shading on panels, the tests have to be performed using a simulator. Therefor this paper derives a new set of relations to simulate the panel’s performance under partial shading conditions and a simulator is constructed accordingly. By holding the temperature constant, the converter’s performance is studied for both uniform illumination and partial shading conditions. Result of studies carried out for uniform illumination under standard conditions and partial shading in conditions under which one third of cells received 600 w/m2 and the rest received 1000 w/m2, indicated a good agreement between the converter’s performance and ideal I-V and P-V curves of solar panel.

Currently, the world is combating with diverse types of challenges related to climate change and fuel costs. However, the research field of the electrical vehicles has given a considerable substitute for conventional vehicles. Moreover, the global involvement in the advancement of Hybrid Electric Vehicles (HEVs) and Plug-in Hybrid Vehicles (PHEVs) is getting higher. The mountaineering prices and reducing oil under the earth is distressing the world’s economy adversely. In 1991, the battery market in the world was estimated to be at $21 Billion Dollars yearly by S.L Deshpande estimated. As of this present day, electric and hybrid electric vehicles have become more protuberant and widely accepted by the public, this indicates the battery market will be more than double the 1991 value by now. Because of the increase in the number of vehicle users, the rate of CO2 emissions has risen, drastically. These discharges, combined with the challenge of coming up with other energy sources for crude oil and natural gas have led to the success of the battery market, most particularly in the EV and HEV business. The demand for ecologically friendly vehicles has risen so that different research works have gone into battery cells technology to produce electric vehicles and to support internal combustion vehicles to form hybrid electric vehicles. The Lithium-ion, Lead-acid, Nickel Metal Hydride, Lithium battery are a few types of batteries used as energy storage systems to drive EV and HEV vehicles. Selection of a battery is based on efficiency, cost, durability, performance, power, energy, etc. This paper seeks to examine and discuss the utilization of different secondary batteries and their use as energy storage systems as well as in EVs and HEVs. The Lithium-ion battery will particularly be the center of discussion in this paper, its role in battery market and economics.

In this paper, a solar micro Combined Cooling, Heating, and Power (mCCHP) system based on ORC cycle is thermodynamically and economically analyzed. The model of conservation of mass, energy, and linear momentum is used to energy analysis of the system. On the other hand, a model based on the first and the second laws of the thermodynamics is used to exergy analysis of the system. Sensitivity analysis of the inlet temperature, back turbine pressure, turbine inlet pressure, and evaporator temperature are considered as the decision variables of the optimization algorithm. The performance of the mCCHP system is determined by some important indices including energy efficiency, exergy efficiency, and investment cost rate. Hence, the three mentioned indices are considered as the objective functions of the optimization. The Particle swarm optimization (PSO) algorithm is used for both single-objective and multi-objective optimization of the system and its code is developed in MATLAB software. The implementation of the multi-objective optimization using PSO for R123 working fluid improves 27.65% thermal efficiency, 27.46% exergy efficiency and reduces 11.98% of the system cost rate.

Parabolic solar system is a non conventional energy system and in this research work performance of parabolic solar system has been optimized. For this, PAPSC software has been designed and developed to analyse the performance of solar collector with and without considering Sun’s cone angle. Developed PAPSC software reduces human effort and eliminates human error. Various parameters have been calculated to analyse the performance of parabolic solar collector; heat gain rates, inlet/outlet temperatures, inner/outer surface areas of absorber pipe, concentration ratios, absorbed fluxes, overall heat loss coefficients, collector efficiency factors, heat removal factors, maximum useful energy available from solar radiation, inlet exergies, outlet exergies, exergy gain rates and exergy efficiencies have been found at different modes of orientations of PSC and then optimum conditions have been identified. This work can be concluded as; mode IV gives maximum exergy efficiency (61.93%) whereas maximum exergy gain rate (2178.10W) achieves with mode III, exergy efficiency increases when instantanious efficiency decreases but not with instantanious beam radiation, inlet exergy decreases with instantanious beam radiation but not with instantanious efficiency whereas outlet exergy decreases when instantanious efficiency increases but not with instantanious beam radiation. Exergies at inlet and outlet increase with dimensions of parabolic solar collector and also with instantanious efficiency but not with instantanious beam radiation.

Solar collectors are a kind of heat exchangers in which solar radiation energy is transmitted to the internal energy of a transferring substance such as water. In any solar system, collectors are the main system of the system. In fact, a solar collector is a device that absorbs and absorbs the sun's intake of radiation energy. This heat is then absorbed, transmitted by a fluid (usually air, water or oil) flowing through the collector. This solar energy is absorbed or converted directly to hot water through a rotating fluid in the collector, or transferred to air conditioners and can easily be consumed. The stored energy can also be stored in a heat storage tank to be used at night or when cloudy sky is used for various uses. In the present study, a laboratory scale was used to construct and evaluate a solar collector and use it to heat the anaerobic digestion reservoirs. The test and test of the collector made in the month of October and the measurement of its thermal efficiency in November 2012 in two sunny and cloudy days. Heating systems in an anaerobic digestion system that operates in an energy-efficient way generate high energy consumption, which is not economically feasible. For this purpose, a collector with rectangular cube plates with dimensions of 50 * 110 cm was designed and tested. The results of the research showed that the collector is well heated with anaerobic digester reservoir and provides a suitable temperature for producing biogas.

This paper presents computational fluid dynamics (CFD) simulation of the solar chimney power plant to analyze to analyze buoyancy-nature of heated air by har- nessing solar energy. ANSYS Fluent a finite volume code has been used for axisym- metric model of the solar chimney power plant (SCPP) prototype in Manzanares, Spain considering updraft tower. A standard k- turbulence model and Boussinesq approximation for buoyancy driven flow is considered. Small pressure difference because of natural draft inside the chimney during day time has been observed due to solar radiation. The numerical results obtained for average velocity and temper- ature at chimney inlet are validated with the experimental results of the prototype. It has been observed that both the velocity and temperature of air inside the SCPP increases significantly with the increment in solar radiation. Increase in the chimney height and collector radius also increases the power output of the plant. The effect of chimney convergence with different area ratio on the power output of SCCPs have been analyzed

A very common technique to improve the thermo hydraulic performance of solar air heater is providing artificial roughness on absorber plate. Diagonally chamfered cuboids has been used to generate roughness and applied on the absorber surface. A numerical study is performed to study the enhancement of the thermo hydraulic performance of the heater for thoroughness parameters of relative roughness pitch (transverse and longitudinal) of 6 to 14, cross section of cuboids from 8 mm to 14 mm and relative roughness height of 0.44 to 0.088. The Reynolds number is kept in the range of 5000 to 22500 with a constant heat flux of 1000 W/m2 on the absorber plate. The numerical computation is conducted by using the ANSYS FLUENT CFD software. The standard k-ε turbulence model with enhanced wall treatment has been used to handle the flow turbulence. The Nusselt number and the average friction factor are determined for different values of relative roughness pitch (transverse and longitudinal), cross section of cuboids and relative roughness height. The values of Nusselt number and friction factor of roughened solar air heater is compared with smooth duct at similar flow condition to find out the enhanced performance.